A Novel Method to Attenuate Protein Adsorption Using Combinations of Polyethylene Glycol (PEG) Grafts and Piezoelectric Actuation

2010 ◽  
Vol 1 (4) ◽  
Author(s):  
Po-Ying Yeh ◽  
Jayachandran N. Kizhakkedathu ◽  
Mu Chiao
Keyword(s):  
Polyethylene Glycol ◽  
Protein Adsorption ◽  
Lead Zirconate Titanate ◽  
Photoelectron Spectroscopy ◽  
Theoretical Calculations ◽  
Lead Zirconate ◽  
Piezoelectric Composite ◽  
Coated Surfaces ◽  
Bsa Adsorption

An antifouling treatment based on the combined effects of grafted polyethylene glycol (PEG) polymers and the application of vibration is reported. A gold-coated lead zirconate titanate piezoelectric composite was grafted with PEG used as a model substrate. The PEG grafted surfaces were thoroughly characterized by attenuated total reflectance-Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. In vitro protein adsorption onto PEG coated surfaces was studied with and without the application of vibration. Bovine serum albumin (BSA) adsorption onto PEG grafted surfaces followed a similar pattern as reported in literature. However, when piezoelectric vibration was applied on the PEG grafted surface, BSA desorption was observed. At very low graft densities, the vibration significantly reduced the BSA adsorption compared with high PEG graft densities. Theoretical calculations showed that the thickness of PEG layer on the surface was affecting vibration induced protein desorption.

A 45 TO 55 Mhz Needle-Based Ultrasound System for Invasive Imaging

1993 ◽  
Vol 15 (1) ◽  
pp. 1-13 ◽  
Author(s):  
G. R. Lockwood ◽  
L. K. Ryan ◽  
F. S. Foster
Keyword(s):  
Lead Zirconate Titanate ◽  
High Frequency ◽  
Imaging System ◽  
Lead Zirconate ◽  
Parabolic Mirror ◽  
Axial Resolution ◽  
Stainless Steel Needle ◽  
Ultrasound System ◽  
Design Construction

The design, construction and fabrication of a high frequency needle-based ultrasound imaging system is described. A miniature lead zirconate titanate transducer was mounted opposite a parabolic mirror in a stainless steel needle. By inserting the needle into a tissue, a cross section image of the tissue can be made. Two needle probes were built, a 45 MHz 2.8 mm diameter probe with 125 μm lateral, 55 μm axial resolution and a 55 MHz 1.6 mm diameter probe with 105 μm lateral, 40 μm axial resolution. Preliminary phantom and in vitro tissue images demonstrate the feasibility of high frequency needle-based imaging.

Lead zirconate titanate aerogel piezoelectric composite designed with biomimetic shell structure for underwater acoustic transducers

2021 ◽  
Author(s):  
Xin Long ◽  
Xiongbang Wei ◽  
Yuhong Qiu ◽  
Ming Jiang ◽  
Zhi Chen ◽  
...  
Keyword(s):  
Lead Zirconate Titanate ◽  
Shell Structure ◽  
Raw Materials ◽  
Composite Coatings ◽  
Sol Gel ◽  
Lead Zirconate ◽  
Piezoelectric Composite ◽  
Gel Method ◽  
Acoustic Transducers ◽  
Zirconate Titanate

In this research, we used lead zirconate titanate (PZT) aerogels prepared by solvothermal assisted sol-gel method as raw materials, and prepared PZT aerogel/PVDF composite coatings and PZT aerogel sintered sheets...

A Study on Long-Term In Vitro Reliability of Intracochlear Lead-Zirconate-Titanate Microactuators

2018 ◽  
Vol 1 (3) ◽  
Author(s):  
Yifeng Liu ◽  
Chuan Luo ◽  
G. Z. Cao ◽  
Clifford R. Hume ◽  
I. Y. Shen
Keyword(s):  
Lead Zirconate Titanate ◽  
Electrical Breakdown ◽  
Failure Mechanisms ◽  
Electrode Array ◽  
Lead Zirconate ◽  
Acoustic Stimulation ◽  
Structural Failure ◽  
Significant Drop ◽  
Zirconate Titanate

An intracochlear lead-zirconate-titanate (PZT) microactuator integrated with a cochlear implant electrode array could be a feasible strategy to implement combined electric and acoustic stimulation inside the cochlea. The purpose of this paper is to characterize in vitro a prototype PZT microactuator for intracochlear applications, including service life, failure mechanisms, and lead leaching. PZT microactuators were driven sinusoidally to failure in air and in artificial perilymph. Frequency response functions (FRFs) and electrical impedance were monitored. After the PZT microactuators failed, the amount of leached lead was measured via inductive coupled plasma mass spectrometry (ICP-MS). Two failure mechanisms are identified: electrical breakdown and structural failure. The electrical breakdown, possibly from loss of parylene encapsulation, is evidenced by a sudden and significant drop of the actuators' electrical resistance. The structural failure, possibly from electrode delamination, is evidenced by a sudden and significant drop of FRFs. The amount of lead leached from the PZT microactuator is well below published safety guidelines from federal agencies.

scholarly journals Mechanical properties and connectivity evaluation of a conductive coated piezoceramic/polymer composite

2014 ◽  
Vol 04 (03) ◽  
pp. 1450019 ◽  
Author(s):  
Gilberto de Campos Fuzari ◽  
Walter Katsumi Sakamoto
Keyword(s):  
Lead Zirconate Titanate ◽  
Polyvinylidene Fluoride ◽  
Volume Fraction ◽  
Composite Films ◽  
Lead Zirconate ◽  
Mechanical Tests ◽  
Piezoelectric Composite ◽  
Mechanical Resistance ◽  
Dielectric Measurements ◽  
Pvdf Matrix

In the present work, piezoelectric composite films made of Polyaniline (PAni) coated Lead Zirconate Titanate (PZT) particles immersed into polyvinylidene fluoride (PVDF) matrix were characterized by mechanical tests, and the connectivity of the composite sample was determined using dielectric measurements and applying the Poon–Shin model. The composite was considered a binary system with coated PZT particles as one phase and the polymer matrix the other one. To support the result obtained from theoretical analysis, scanning electron microscopy of the composites were done. It was observed a decrease up to 85% on the mechanical resistance when the ceramic volume fraction increases from 0% to 40%. Furthermore, the composite film no longer can be considered with 0–3 connectivity when the ceramic content is 30 vol.% or over.

scholarly journals Magnetodielectric properties of ferrite-piezoelectric composite materials.

2021 ◽  
Vol 2021 (10) ◽  
Author(s):  
Yu.A. Lupitskaya ◽  
◽  
E.M. Filonenko ◽  
P.E. Romazev ◽  
◽  
...  
Keyword(s):  
Composite Materials ◽  
Lead Zirconate Titanate ◽  
Ceramic Composite ◽  
Lead Zirconate ◽  
Piezoelectric Composite ◽  
Entire Concentration Range ◽  
Physicochemical Methods ◽  
System 1 ◽  
Different Content ◽  
Frequency Dependences

Ceramic composite materials based on compounds of lead zirconate-titanate and cobalt ferrite with different content of the initial components mass fraction have been synthesized. Using a complex of physicochemical methods, the microstructure and magnetodielectric properties of the synthesized ceramics have been studied. The resulting frequency dependences of the magneto-dielectric coefficient for the composite system (1-x)PZT + xCF(0.0 ≤ x ≤ 0.5) in an external magnetic field have a resonance form in the entire concentration range investigated. The largest changes in the value of the complex permittivity are observed for the sample with the composition of 0.6PZT + 0.4CF.

Assessment of human bones encompassing physiological decay and damage using piezo sensors in non-bonded configuration

2017 ◽  
Vol 28 (14) ◽  
pp. 1977-1992 ◽  
Author(s):  
Shashank Srivastava ◽  
Suresh Bhalla ◽  
Alok Madan
Keyword(s):  
Lead Zirconate Titanate ◽  
Mechanical Impedance ◽  
Lead Zirconate ◽  
Biomedical Sensors ◽  
Human Bones ◽  
Zirconate Titanate ◽  
Artificial Bones ◽  
Sensor Configuration

In the recent years, several biomedical applications of lead zirconate titanate piezo-electric ceramic patches based on the electro-mechanical impedance technique have been reported in the literature. However, practical application of the technique on live subjects is severely hampered due to the requirement of bonding the patch with bone or cartilage with an adhesive. In addition, live subjects have skin cover over the bone. This article proposes and evaluates the feasibility of employing lead zirconate titanate patches as biomedical sensors in non-bonded configuration for assessing the physiological conditions of bones. For this purpose, a special design is proposed where the lead zirconate titanate patch is first bonded on a thin aluminum strip, which is in turn clamped securely on the biomedical subject. The proposed configuration is investigated both in vitro and in vivo. The non-bonded piezo sensors are first investigated to identify dynamic parameters of the bone through lab-based experimental study involving artificial bones. Thereafter, physiological damage and decay conditions are artificially simulated in the experimental bones and the same are correlated with changes in conductance signatures from the non-bonded piezo sensor as well as the lead zirconate titanate patch in the conventional adhesively bonded (direct bonding to the subject) configuration. The trend of the conductance signatures in the healthy and the damaged conditions from the non-bonded piezo sensor is found to correlate well with the corresponding signatures from the directly bonded piezo sensor. At the same time, the repeatability of the signatures is also found to be satisfactory. After success in bare bones, the non-bonded piezo sensor configuration is extended to monitor the condition of bones covered with skin and tissue, simulated in the lab with the aid of silicone-based coating. Finally, a proof-of-concept experiment on a live human subject is successfully demonstrated. The overall results of the study demonstrate very good prospects of employing lead zirconate titanate patches in non-bonded piezo sensor mode for monitoring the condition of human bones and other related biomedical subjects.

scholarly journals Physical Gold Nanoparticle-Decorated Polyethylene Glycol-Hydroxyapatite Composites Guide Osteogenesis and Angiogenesis of Mesenchymal Stem Cells

Biomedicines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1632
Author(s):  
Chiung-Chyi Shen ◽  
Shan-Hui Hsu ◽  
Kai-Bo Chang ◽  
Chun-An Yeh ◽  
Hsiang-Chun Chang ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Polyethylene Glycol ◽  
Osteogenic Differentiation ◽  
Photoelectron Spectroscopy ◽  
In Vivo Evaluation ◽  
Vitro Assay ◽  
Vis Spectroscopy

In this study, polyethylene glycol (PEG) with hydroxyapatite (HA), with the incorporation of physical gold nanoparticles (AuNPs), was created and equipped through a surface coating technique in order to form PEG-HA-AuNP nanocomposites. The surface morphology and chemical composition were characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), UV–Vis spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and contact angle assessment. The effects of PEG-HA-AuNP nanocomposites on the biocompatibility and biological activity of MC3T3-E1 osteoblast cells, endothelial cells (EC), macrophages (RAW 264.7), and human mesenchymal stem cells (MSCs), as well as the guiding of osteogenic differentiation, were estimated through the use of an in vitro assay. Moreover, the anti-inflammatory, biocompatibility, and endothelialization capacities were further assessed through in vivo evaluation. The PEG-HA-AuNP nanocomposites showed superior biological properties and biocompatibility capacity for cell behavior in both MC3T3-E1 cells and MSCs. These biological events surrounding the cells could be associated with the activation of adhesion, proliferation, migration, and differentiation processes on the PEG-HA-AuNP nanocomposites. Indeed, the induction of the osteogenic differentiation of MSCs by PEG-HA-AuNP nanocomposites and enhanced mineralization activity were also evidenced in this study. Moreover, from the in vivo assay, we further found that PEG-HA-AuNP nanocomposites not only facilitate the anti-immune response, as well as reducing CD86 expression, but also facilitate the endothelialization ability, as well as promoting CD31 expression, when implanted into rats subcutaneously for a period of 1 month. The current research illustrates the potential of PEG-HA-AuNP nanocomposites when used in combination with MSCs for the regeneration of bone tissue, with their nanotopography being employed as an applicable surface modification approach for the fabrication of biomaterials.

Sign in / Sign up

Export Citation Format

Share Document